package com.zhang.util;

import java.awt.*;
import java.util.Random;

/**
 * @author zhang
 * @time 2022/02/03 08:17:40
 */
public class RandomValidateCode {
    //放到session中的key
    public static final String RANDOMCODEKEY = "RANDOVALIDATECODEKEY";
    //随机产生数字和字母的组合
    private String randString = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";

    //字符串
    private int width = 95;// 图片宽
    private int height = 25;// 图片高
    private int lineSize = 10;// 干扰线数量
    private int stringNum = 4;// 随机产生字符数量

    private Random random = new Random();
    /*
     * 获得字体
     */
    private Font getFont() {
        return new Font("Fixedsys", Font.CENTER_BASELINE, 24);
    }

    /*
     * 获得颜色
     */
    public Color getRandColor(int fc, int bc) {
        if (fc > 255)
            fc = 255;
        if (bc > 255)
            bc = 255;
        int r = fc + random.nextInt(bc - fc - 16);
        int g = fc + random.nextInt(bc - fc - 14);
        int b = fc + random.nextInt(bc - fc - 18);
        return new Color(r, g, b);
    }

    /*
     * 绘制字符串
     */
    public String drowString(Graphics g, String randomString, int i) {
        g.setFont(getFont());
        g.setColor(new Color(random.nextInt(101), random.nextInt(111), random
                .nextInt(121)));
        String rand = String.valueOf(getRandomString(random.nextInt(randString
                .length())));
        randomString += rand;
        g.translate(random.nextInt(3), random.nextInt(3));
        g.drawString(rand, 13 * i, 16);
        return randomString;
    }

    /*
     * 绘制干扰线
     */
    public void drowLine(Graphics g) {
        int x = random.nextInt(width);
        int y = random.nextInt(height);
        int xl = random.nextInt(13);
        int yl = random.nextInt(15);
        g.drawLine(x, y, x + xl, y + yl);
    }

    /*
     * 获取随机的字符
     */
    public String getRandomString(int num) {
        return String.valueOf(randString.charAt(num));
    }

}
